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Real-time algorithm for retinal tracking.

M S Markov·H G Rylander·A J Welch
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Abstract

Conventional retinal laser photocoagulation is presently performed by an ophthalmologist manually aiming a low-power laser beam at a desired site and firing a high-power laser for a preselected interval of time. To automate this process a retinal tracker must acquire a target, track small saccades, and identify loss of track during a large saccade. The authors successfully implemented a real-time algorithm that used a simple computer, video digitizing card, low light video camera, and fundus camera to perform rudimentary tracking on a photograph of a retina undergoing smooth circular motion. The algorithm tracked speeds up to 5 Hz, or 27 degrees/s, which equated to the retina moving in a 525 microns diameter circle.

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AlgorithmsEquipment DesignFalse Positive ReactionsFundus OculiHumansLaser CoagulationMathematicsRetinaRetinal VesselsSaccadesSignal Processing, Computer-AssistedJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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M S Markov, H G Rylander, A J Welch. 1993. Real-time algorithm for retinal tracking.. https://doi.org/10.1109/10.250583

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